28 
Bulletin 1356, U. S. Department of Agriculture 
The beneficial effect of the organic matter in the soil was also shown 
in other ways. Where soybeans had been grown moisture was more 
effectively retained in the soil during and immediately after seeding. 
It was therefore seldom necessary to apply irrigation water earlier 
than 30 days after emergence of the rice plants. The early growth 
of the crop also was very vigorous, which indicated greater fertility 
and generally improved soil conditions. 
When grown in rotation with rice, soybeans should be sown on 
land plowed during the previous winter to a depth of at least 5 
inches. The plowed land should be disked several times in the 
spring before seeding. This tillage has an important bearing on 
Fig. 9. — A plat of Biloxi soybeans at the Rice Experiment Station, Crowlev, La, 
October 2, 1919. The seed was sown June 15, and the beans were harvested 
November 10 
the control of weeds. If repeated several times during April and 
early May, weeds of many species and especially red rice will be 
destroyed before the soybean crop is sown. 
_ Sowing soybeans on high ridges, as is done with corn in this sec- 
tion of Louisiana, is not desirable. The high ridges interfere with 
cultivating and harvesting the crop. A slight ridge, however, may 
be an advantage in preventing water from settling on the seed 
usually pulverizes the soil so well that the only additional prepara- 
tion required before seeding is to level the ridges slightly with a 
drag or float. & J 
Experiments show that soybeans should be sown in rows 4 feet 
apart and at the rate of 30 pounds of seed per acre. Seeding may 
